CVE-2026-73436 Security Advisory 0171
A crafted OSPFv2 packet can cause the OSPF process to restart, leading to a denial of service on Arista EOS devices.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-73436?
CVE-2026-73436 is a medium-severity denial of service vulnerability in Arista Networks EOS, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
On affected platforms running Arista EOS with OSPFv2 and OSPFv2 segment routing configured, a specially crafted OSPFv2 packet from an adjacent OSPF neighbor may cause OSPF to restart unexpectedly.
Which versions are affected by CVE-2026-73436?
How do I fix CVE-2026-73436?
No fix has been published for CVE-2026-73436 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-73436 being exploited?
There is no known exploitation of CVE-2026-73436 in the wild and no public exploit code.
Sources
Also known as GHSA-j872-p7vg-jj85.